Train-control device



T 1,569,155 T. H. THOMAS TRAIN CONTROL DEVICE Filed March 24, 1924 W Ai n MA

INVENTOR L Ej THOMAS HTHQMAS @B924 ATTORNEY Patented l2, 19.26.

UNlTD SFr/tall? Five j.

PATENT orales.

THOMAS H. THOMAS, OF EDGEWOGD, ENNSYLVANIA, ASSIGNQR T THE "WESTING- HOUSE AIR BRAKE COMPANY, OF /VLMERDNG, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA,

TRAIN-GQ19293301: DEVICE.

Application filed March 24, 1924. Serial No. 701,377.

To all ill/rom it may concern.'

Be it known that I, THOMAS H. Trroinis,

" a citizen ofthe United States, residing at Edgewood, in the county of Allegheny and Stat-'e of` Pennsylvania, have invented new and'useful linprovements in Train-Control Devices, of which the following is a speciiication.

This invention relates to automatic train control systems, and more particularly to those in which the speed of the train is controlled in accordance with the signal indication.

lilith a train speed control equipment, a centrifugal governor is usually employed, which is responsive to the speed of the train for controlling apparatus by which the speed of the train is limited.

If the speed governor should fail, as by the breaking of the governor shaft, for eX- ample, then the speed control apparatus would fail to function as intended.

The principal object of my invention is to provide means operative upon failure of the speed governor for reducing the speed of the train.

ln the accompanying drawing; Fig. 1 is diagrammatic view of mechanism for limiting the speed of the train, in case of failure of the speed governor, in accordance juith my invention; Fig. 2 a section on the line 2-2 of 1; Fig. 3 a section on the line 3 3 of Fig. 1; Fig. 4 a section on the line 4-4 of Fig. 1; Fig. 5 a section on the line 5 5 of Fig. 1; and Fig. 6 a developed view of the contact segments of the contact drums shown in Fig. 1.

fis shown in Fig. 1, the shaft 1 is operatively connected so as to rotate when the speedA governor (not shown) of the speed control apparatus rotates, while the shaft 2 is operatively connected so as to rotate when the locomotive axle, or other rotating part of tlie locomotive, rotates.

.fri'iplied to the shaft 1 is a drum 3 of insulating material and carried by said drum are continuous contact rings 4, 5, and and alined contact segments 7, 8, and 9, the contact rings 4, 5, and 6 being electri- .cally connected to the respective contact segments 7, 8, and 9,

Applied to Shaft 2 is a drum 10 of inf -sulating material and carried by said drum :are continpnus contact rings 11, 12, and 13,

and alined Contact segments 14, 15, and 1G, which are electrically connected to the respective contact rings 11, 12, and 13.

Contact fingers 17, 18, and 19 engage the respective contact rings 4, 5, and G and contact finger 2O engagesthe contact segments 7, 3, and 9. Contact fingers 21, 22, and 23 engage the Contact rings 11, 12, and 13 and contact finger 24 engages the contact segments 14, 15, and 16. The contact lingers 17, 18, and 19 are electrically connected to the respective contact fingers 21, 22, and 23 and the contact finger 2O is connected to one terminal of an electro-magnet 25. The contact linger 24 is connected to a source of current 26 which is in circuit with the magnet 25.

A brake application valve device 27 is provided, which may be the usual brake application valve device of the train speed control equipment and said valve device may comprise a casing having a piston chamber 28 containing a piston 29 and a valve chamber 30 containing a slide valve 31 adapted to be operated by piston 29.

The valve chamber 30 is connected to a source of fluid under pressure, such as the reservoir 32 and Huid equalizes from chamber 30 through a restricted port 33 into piston chamber 28. With the fluid pressures equalized on opposite sides of piston 29, the spring 34 maintains the piston 29 in release position, as shown in Fig. 1.

The magnet 25 controls a valve 35 and when the magnet is deenergized, the Ivalve V35 is unseated, so that fluid under pressure will be vented from piston chamber 28.

The shaft 1 which rotates when the speed governor shaft rotates and the shaft 2 which rotates when the locomotive axle rotates are so geared that both shafts rotate at the same speed and the contact drums 3 and 1() are so positioned that the contact linger 2O will successively engage the contact segments 9, 8, and 7 at the same time that the contact linger 24 successively engages the contactsegments 16, 15, and 14 when the drums 3 and 10 are rotated at the same speed and in the same direction.

Taking the position shown in Fig. 1, the contact finger 2O engages the contact seg" ment 9, while contact finger 24 engages the segment 16 and by reference to Fig. 6, it Willb@ Cll @het a Gironi@ iS Completed from linger 20, through contact segment 8, ring 5, ring 12, and segment l5, to linger 24. In the same way, when the fingers 2O and 24 pass to the segments 7 and 14, the circuit is completed from finger 20, through contact segment 7, ring 4, ring 11, and segment 14 to finger 24.

It will thus -be seen .that so long as the shafts 1 and 2 and the drums 3 and 10 rotate in synchronism, the circuit of the magnet 25 will be maintained and said magnet will remain energized, rand so long as the magnet 25 lis energized, the valve 35 is held seated and no 'action takes place.

If, however, the shaft l -shouldcease rotating, while the shaft 2, rotating with the locomotive axle, continues to rotate, then as soon as the :rotating drum 10 Vhas rotated so that the contact finger 24 passes out of engagement with the contact segment corresponding 'with the `contact segment with which the finger 20 engages, the .magnetcircuit will be broken. For example, assume that the drum 3 ceases to `rotate while the contact vfinger 20 .engages the segment 9,

'then the drum 10, continuing-to rotate, causes the contact segment ,16 to move out of engagement with the contact finger 2.4, and

thus open the magnet circuit.

VWhen the magnet 2 5 becomes deenergized by the 'openingof the lmagnet circuit, the valve 85 will be unseated, so-that fluid will be vented from the pistonchamber 28. The

vpiston 29 is then operatedandthe slide valve is shifted to-connectfthe usual train brake pipe 36 throughcavity 37 with an exhaust port 38. vFluid under pressure is conse- .quently vented from thelbrake pipe to effect an application of the Vbrakes in the usual manner.

It is possible that thefdrum 3 may cease rotating when thecontact linger 20 happens to bridge adjacent contactlsegzg'ments,` and if each drum were only provided with two contact segments and two contact rings, the circuit would not be broken by the continual rotation of the -drum '10, since the circuit wouldbe maintained through eitherone or the other of the twocontact `segments on thedrum 3, both ofthe segments being con- ;nected to the finger 20.

For the above reason, it is preferable to provide threeor more contact segments on each drum, so that there will always adapted to maintain an electric circuit continnously closed so long as said elements rotate in synchronism, the circult being opened upon failure of one element to rotate.

2. In an electric circuit controlling mechanism, the combination with two synchronously rotating elements, of electric switch members associated with each element and adapted to maintain an electric circuit continuously closed so long as said elements rotate in synchronism, the circuit being opened by the continued rotation of one element upon failure of the other element to rotate.

3. In an electric circuit controlling mechanism, the combination with two rotating elements, of a plurality of contact segments associated with one element, .contact segments associated with the other element and electrically connected to corresponding contact segments of the first eleme-nt, and a contactmember engaging a corresponding connected segment of each element to continuously close an lelectric circuit so long as both elements rotate.

4. In an electric circuit controlling mechanism, the combination with two rotating elements, of a plurality of contact segments associated with one element, contact segments associated with the other element and electrically connected to corresponding contact segments of the first element, and a contact member engaging a corresponding connected segment of each element to continuously maintain an electric circuit closed so long as-both elements rotate in synchronism.

5. vIn an electric circuit controlling device, the combination with two synchronously rotatable elements, of a plurality of contact members carried by one element, contact members carried by the other element and each electrically connected to a corresponding contact member of the first rotatable element, and a contact finger adapted to engage the contact members of each rotatable element, said fingers being positioned to encorresponding connected contact members and continuously maintain an electric circuit closed, so long as said elements rotate in synchronism.

6. In a train controlapparatus. the combination with electrically controlled means operating upon deenergization for effecting an application of the brakes, of two rotatable elements adapted to rota-te in synchronism and switch mechanisms associated with each element for maintaining the circuit of said means closed so long as both elements rotate in synchronism, said circuit being opened upon failure of one element to rotate` 7. In a train control apparatus, the combination with a brake application valve device operating upon a reduction in Huid pressure for effecting an application ofthe brakes, a magnet, and a valve operated upon deenergization of said magnet for venting fluid from said valve device, of' tivo elements adapted to rotate in synchronisin, a plurality of contact segments carried by one ele-ment, a plurality of contact segments carried by the other element and each electrically connected to a corresponding segment of the other element, and a contact finger for each element in circuit with said magnet and adapted to engage corresponding Contact segments o1 each element to maintain said circuit closed, so long as said elements rotate in synchronism.

8. In an electric circuit controlling device, the combination with tivo rotating` elements, oi a plurality of continuous contact rings carried by cach element, a contact linger engaging each ring, each Contact finger of one element being connected to a contact finger of the other ele-ment, contact segments carried by each element and each connected to a corresponding contact ring, and a contact iinger engaging the contact segments of each element and connected to anelectric circuit.

In testimony whereof I have hereunto set my hand. K

THOMAS H. THOMAS. 

